JP4288700B2 - Programmable controller - Google Patents

Description

  The present invention relates to a programmable controller, and more particularly to a programmable controller that can shorten the IO data update processing time.

  The following are examples of prior art documents related to the programmable controller as assumed by the present invention.

JP 2003-271210 A

  FIG. 7 shows the configuration of the programmable controller. The programmable controller includes a CPU module 4 and a plurality of IO modules 5, and these modules are connected by a bus 7. The high-function IO module 6 is an IO module having an arithmetic function and is used as necessary.

  The IO module 5 (or the high-function IO module 6) takes in a signal from a sensor or the like (not shown) and outputs a control signal to an actuator (not shown). The CPU module 4 updates the data of the IO module 5 by executing a program stored therein.

  FIG. 8 shows the operation of the CPU module 4. The operation of the CPU module 4 can be divided into a program execution process performed by the instruction execution processing unit and an IO data update process performed by the IO data update processing unit. First, a program execution process for executing a program stored therein is performed, and then an IO data update process for reading and writing data to / from the IO module 5 (or the high-function IO module 6) via the bus 7 is performed. Is called.

  This program execution process and IO data update process are repeatedly executed. One of these repetitions is called one scan. The program is divided into program blocks for each processing unit, and can be started and stopped for each program block.

  The IO data update process is performed using an IO update table. FIG. 9 shows the configuration of the IO update table. The IO update table 8 includes an IO module number 81 used in the entire program and an IO channel number 82 included in each IO module. In the IO data update process, the data of the IO module and IO channel specified in the IO update table 8 is updated in order for each scan.

  However, such a programmable controller has the following problems. The IO data update processing is executed for every scan for all IO modules and IO channels whose numbers are stored in the IO update table 8 regardless of whether or not the IO data is actually updated. To do.

  The IO update table 8 stores the numbers of all IO modules and IO channels that may be accessed by the program. Therefore, the data update process is executed also for the IO modules and IO channels whose data has not been updated by the scan. As a result, since the maximum data is always transferred to the bus 7, there is a problem that it takes time to update the data and the scan time becomes long.

  Therefore, the problem to be solved by the present invention is to provide a programmable controller capable of reducing the bus transfer amount and the scan time by not performing the data update process of the IO whose data is not updated.

In order to achieve such a problem, the invention according to claim 1 of the present invention repeats the operation of dividing the program into a plurality of program blocks and executing the update processing of IO data after executing these program blocks. In the programmable controller,
An overall IO update table storing an IO unit identification symbol in which IO data may be updated in any one of the program blocks, and provided for each IO unit identification symbol in the entire IO update table And a counter that is set to the first value at the time of startup, and a block IO update table that is provided for each program block and stores an IO unit identification symbol that may update IO data in the program block When the program block is executed in order and the program block is activated, the block IO update table of the program block is referenced to correspond to the identification unit of the IO unit stored in the block IO update table When adding a second value to the counter to stop the program block An instruction execution processing unit for subtracting the second value from the counter corresponding to the identification symbol of the IO unit stored in the block IO update table with reference to the block IO update table of the program block; Referring to the counter, when the counter is not the first value, the IO data update process corresponding to the counter is executed, and when the counter value is the first value, And an IO data update processing unit that does not execute the corresponding IO data update processing of the IO unit. The time for IO update processing can be shortened.

According to a second aspect of the invention, in the first aspect of the invention, the counter is built in the overall IO update table. Configuration is simplified.

According to a third aspect of the invention, in the first or second aspect of the invention, the IO unit is an IO channel unit included in an IO module .

  According to a fourth aspect of the invention, in the first or second aspect of the invention, the IO unit is an IO module unit.

The invention according to claim 5 is a programmable controller that is divided into a plurality of program blocks and repeats an operation of performing update processing of IO data after executing these program blocks.
An entire IO update table storing an IO unit identification symbol in which IO data may be updated in any of the program blocks, and provided for each IO unit identification symbol in the entire IO update table Flag, a block IO update table that is provided for each program block and stores an IO unit identification symbol in which IO data may be updated in the program block, and all before executing the program block When the program block is executed with the flag set to the first value, the block IO update table of the program block is referenced to correspond to the identification unit of the IO unit stored in the block IO update table An instruction execution processing unit that sets the flag to a second value and the flag are referred to. When the flag is the second value, an IO unit IO data update process corresponding to the flag is executed. When the flag value is the first value, the IO unit corresponding to the flag is updated. And an IO data update processing unit that does not execute the IO data update process. The time for IO update processing can be shortened.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the flag is incorporated in the overall IO update table. Configuration is simplified.

The invention according to claim 7 is the invention according to claim 5 or 6 , characterized in that the IO unit is an IO channel unit included in an IO module .

The invention according to claim 8 is the invention according to claim 5 or 6 , wherein the IO unit is an IO module unit.

The invention according to claim 9 is the invention according to claim 5 or 8 , wherein the program block is divided for each IO unit. The number of IO units for data update can be reduced.

As is apparent from the above description, the present invention has the following effects.
According to the first, second, third, and fourth aspects of the present invention, a counter is provided for each IO unit, and when the program block is started, the second value is added to the counter, and when the program block is stopped. The second value is subtracted from the counter so that the IO data update process of the IO corresponding to the counter is performed only when the counter value is not the first value.

  By not performing the IO data update processing for the IO units used in the stopped program blocks, the number of IO units for data update can be reduced. For this reason, the amount of data transferred on the bus can be reduced, the time required for the update process can be shortened, and the scan time can be shortened.

According to the fifth, sixth, seventh, eighth, and ninth aspects of the present invention, a flag is provided for each IO unit, and the flag is set to the first value at the beginning of scanning, and the flag is executed when the program block is executed. Is set to the second value, and the IO data update process of the IO unit corresponding to the flag is performed only for the IO unit whose flag is the second value.

  By not performing the IO data update processing for the IO units used in the program blocks that are not executed, the number of IO units for data update can be reduced. For this reason, the amount of data transferred on the bus can be reduced, the time required for the update process can be shortened, and the scan time can be shortened. In addition, there is an effect that the configuration is simplified compared to the case where a counter is used.

  Furthermore, by dividing the program block for each IO unit, the number of IO units for updating data in a plurality of program blocks can be reduced, so that the time required for data update can be further reduced.

  Hereinafter, the present invention will be described in detail with reference to the drawings. As described in the background art, also in this embodiment, the program is divided into program blocks for each processing unit, and these program blocks can be started and stopped individually. Also in this embodiment, as shown in FIG. 8, after the program execution process is performed by the instruction execution processing unit, the scan for performing the IO data update process by the IO data update processing unit is repeated.

  Further, in this embodiment, IO data update processing is executed using one overall IO update table and a block IO update table provided for each program block.

  FIG. 1 is a diagram showing the configuration of the entire IO update table. The entire IO update table stores IO modules and IO channel numbers that may be accessed by the entire program, and counters associated with each IO channel number. The IO module number and IO channel number are used as identification symbols.

  In FIG. 1, 1 is an overall IO update table. Reference numeral 11 denotes an IO module number, which stores the number of an IO module that may be accessed by the entire program. In FIG. 1, numbers from IO modules 1 to n are stored.

  Reference numeral 12 denotes an IO channel number, which stores an IO channel number that is included in each IO module and may be accessed by the entire program. In FIG. 1, IO channel numbers 1 to m are stored for the IO module 2.

  In this figure, only the number of the IO channel included in the IO module 2 is shown, but actually the IO module 1 and the IO modules 3 to n are also included in the IO module and accessed by the entire program. Stores the number of possible IO channels. A counter 13 is provided for each IO channel number. A counter is also provided for each IO channel number not shown in FIG.

  By examining the value of this counter, it is possible to know whether or not the IO channel has been accessed. This counter 13 is initialized to zero when the entire program is started.

  FIG. 2 shows a configuration of a block IO update table provided for each program block. This block IO update table stores the numbers of all IO modules and IO channels that may be accessed in the program block.

  In FIG. 2, 2 is a block IO update table. Reference numeral 21 denotes an IO module number, which stores the number of an IO module that may be accessed by the program block. In FIG. 2, the numbers of the IO modules 1 to p are stored.

  Reference numeral 22 denotes an IO channel number, which stores the number of an IO channel that is included in each IO module and may be accessed by the program block. In FIG. 2, the numbers of IO channels 1 to q are stored for the IO module 2.

  Although not shown in FIG. 2, the numbers of IO channels that are included in the IO module and may be accessed by the program block are also stored for the IO modules 1, 3 to p.

  FIG. 3 shows a flowchart of processing when each program block is started and stopped. In FIG. 3, (A) is a flow when the program block is activated, and (B) is a flow when it is stopped. When starting, the block IO update table 2 belonging to the program block is referred to, and 1 is added to the counter 13 of the overall update table for all registered IO channels.

  When stopping a program block, 1 is subtracted from the counter 13 of the entire update table for all registered IO channels with reference to the block IO update table 2 belonging to the program block.

  That is, when the program block is activated, the count value of the counter 13 attached to the IO channel that may be accessed by the program block increases by 1, and when the program block stops, it decreases by 1.

  Since one IO channel may be accessed by a plurality of program blocks, if the counter value is not zero, the IO channel may be accessed by any program block, and if it is zero, all programs will be accessed. It can be seen that there is no possibility of being accessed in blocks.

  FIG. 4 is a flowchart showing the flow of IO data update processing. In FIG. 4, it is checked in (4-1) whether the value of the counter 13 attached to the IO channel is zero. If it is not zero, the data update process for the IO channel is performed in (4-2), and if it is zero, the data update process for the IO channel is not performed in (4-3). Then, in (4-4), it is confirmed whether all counters 13 have been checked. If checked, the process ends. If there is a counter 13 that has not been checked, the process returns to (4-1).

  As described above, the count value of the counter attached to the IO channel that cannot be accessed becomes zero. Therefore, by performing the process shown in the flowchart of FIG. 4, it is possible to prevent the data update process of the IO channel that is not likely to be accessed. Therefore, the data transfer amount can be reduced, and the scan time can be shortened. Note that the initial value of the counter may not be zero, and the value to be added or subtracted may not be 1.

  5 and 6 show another embodiment of the present invention. FIG. 5 shows the configuration of the entire IO update table. In addition, the same code | symbol is attached | subjected to the same element as FIG. 1, and description is abbreviate | omitted. In FIG. 5, reference numeral 3 denotes an entire IO update table, in which an IO module number 11 and an IO channel number 12 are stored.

  Reference numeral 31 denotes a flag, which is provided in each IO channel in place of the counter 13 of FIG. The flag 31 is a 1-bit register and takes two values, on and off. The block IO update table is the same as in FIG.

  FIG. 6 shows a flowchart for explaining the operation of this embodiment. This flowchart represents the operation of one scan. First, all the flags 31 are turned off in (6-1). Next, a program execution process is performed in (6-2).

  At this time, referring to the block IO update table of the program block in each program block, the flag 31 attached to the IO channel registered in the block update table is turned on. Similarly, when the program block is newly activated, the flag 31 is turned on.

  When the program execution process ends, the IO data update process is performed. In (6-3), it is checked in turn whether the flag 31 of the overall update table 3 is on. If it is on, the IO data update processing for that channel is performed in (6-4), and if it is off ( The update process is not performed in 6-5).

  Next, it is checked whether or not all the flags 31 have been checked in (6-6). If there is an unchecked flag, the process returns to (6-3), and if all the flags 31 have been checked, the IO data is updated. End the process and execute the next scan. By doing so, it is possible to prevent the update process of the IO channel that is not likely to be accessed, so that the scan time can be shortened. Note that the on / off of the flag may be reversed.

  In these embodiments, if a plurality of program blocks share an IO channel, the data update process for that IO channel is performed unless all the shared program blocks stop. Therefore, it is possible to reduce the time for IO update processing by creating a program block for each IO channel so that a plurality of program blocks do not share the IO channel.

  In these embodiments, the counter 13 or the flag 31 is provided for each IO channel. However, the counter 13 or the flag 31 may be provided for each IO module or IO terminal, or for each other IO unit.

It is a block diagram of a whole IO update table. It is a block diagram of a block IO update table. It is a flowchart which shows the process at the time of starting and a stop of a block program. It is a flowchart of IO update processing. It is a block diagram of the whole IO update table of another Example. It is a flowchart of IO update processing of another Example. It is a block diagram of a programmable controller. It is a flowchart which shows operation | movement of a programmable controller. It is a block diagram of the conventional IO update table.

Explanation of symbols

1, 3 Overall IO update table 11, 21 IO module number 12, 22 IO channel number 13 Counter 2 Block IO update table 31 Flag

Claims (9)

In a programmable controller that divides a program into a plurality of program blocks and repeats an operation of updating IO data after executing these program blocks,
An overall IO update table storing an IO unit identification symbol in which IO data may be updated in any of the program blocks;
A counter that is provided for each IO unit identification symbol in the overall IO update table and is set to a first value at startup;
A block IO update table that is provided for each program block and stores an IO unit identification symbol in which IO data may be updated in the program block;
When the program blocks are executed in order and the program block is activated, the block IO update table of the program block is referred to and the IO unit identification symbol stored in the block IO update table is stored. When a second value is added to the counter and the program block is stopped, the block IO update table of the program block is referred to, and the IO unit identification symbol stored in the block IO update table is corresponded An instruction execution processing unit for subtracting the second value from the counter;
Referring to the counter, when the counter is not the first value, an IO data update process corresponding to the counter is executed, and when the counter value is the first value, the counter An IO data update processing unit that does not execute IO data update processing in IO units corresponding to
A programmable controller comprising: 2. The programmable controller according to claim 1, wherein the counter is built in the overall IO update table. The programmable controller according to claim 1, wherein the IO unit is an IO channel unit included in an IO module . 3. The programmable controller according to claim 1, wherein the IO unit is an IO module unit. In a programmable controller that is divided into a plurality of program blocks and repeats an operation of performing update processing of IO data after executing these program blocks,
An overall IO update table storing an IO unit identification symbol in which IO data may be updated in any of the program blocks;
A flag provided for each IO unit identification symbol in the overall IO update table;
A block IO update table that is provided for each program block and stores an IO unit identification symbol in which IO data may be updated in the program block;
Before executing the program block, all the flags are set to the first value, and when the block program is executed, the block IO update table of the program block is referred to and stored in the block IO update table. An instruction execution processing unit that sets the flag corresponding to the identification symbol in the IO unit to a second value;
The flag is referred to, and when the flag is the second value, the IO data update process of the IO unit corresponding to the flag is executed, and when the flag value is the first value, An IO data update processing unit that does not execute IO data update processing in units of IO corresponding to the flag;
A programmable controller comprising: 6. The programmable controller according to claim 5 , wherein the flag is built in the overall IO update table. The IO unit according to claim 5 or claim 6 programmable controller, wherein the a IO channel units contained in the IO module. Claim 5 or claim 6 programmable controller, wherein said IO units are IO module units. 9. The programmable controller according to claim 5 , wherein the program block is divided for each IO unit.

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